Shareholder Fees	Jul. 29, 2026 USD ($)
Buffalo Blue Chip Growth Fund \| Buffalo Blue Chip Growth Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	$ 0
Buffalo Blue Chip Growth Fund \| Buffalo Blue Chip Growth Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Early Stage Growth Fund \| Buffalo Early Stage Growth Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Early Stage Growth Fund \| Buffalo Early Stage Growth Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Flexible Allocation Fund \| Buffalo Flexible Allocation Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Flexible Allocation Fund \| Buffalo Flexible Allocation Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Growth Fund \| Buffalo Growth Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Growth Fund \| Buffalo Growth Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Growth & Income Fund \| Buffalo Growth & Income Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Growth & Income Fund \| Buffalo Growth & Income Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo High Yield Fund \| Buffalo High Yield Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo High Yield Fund \| Buffalo High Yield Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo International Fund \| Buffalo International Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo International Fund \| Buffalo International Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Mid Cap Discovery Fund \| Buffalo Mid Cap Discovery Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Mid Cap Discovery Fund \| Buffalo Mid Cap Discovery Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Mid Cap Growth Fund \| Buffalo Mid Cap Growth Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Mid Cap Growth Fund \| Buffalo Mid Cap Growth Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Small Cap Growth Fund \| Buffalo Small Cap Growth Fund Investor Class
Prospectus [Line Items]
Shareholder Fee, Other	0
Buffalo Small Cap Growth Fund \| Buffalo Small Cap Growth Fund Institutional Class
Prospectus [Line Items]
Shareholder Fee, Other	$ 0

Buffalo Blue Chip Growth Fund | Buffalo Blue Chip Growth Fund Investor Class